Stylus for talking-machines and process of making same.



WHITEMAN, JR. STYLUS FOR TALKING MACHiNES AND PROCESS OF MAKING SAME.

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APPLICATION FILED NOV- 27. I914- Patented Sept. 5. 1916.

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STYLUS FOR TALKING-MACHINES AND PROCESS OF MAKING SAME.

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Speciflcatioetters Patent. mmmu 5, 19 m Applioationfiled November 27, 1914. Serial No. 874,331.

My invention relates to talking machinesand comprises a novel stylus or reproducer point for use in such apparatus, and a-novel process of making the same.

The ordinary stylus made of metal or other hard substance is apt to cut or. wear out the record groove in a'sound' record tablet too rapidly and also to produce scratching sounds which are objectionable as interfering with the accuracy of the sound reproduction. On the other hand, reproducer needles orstylus points made of wood,

to reduce the scratching sounds and the' friction on the sound records, are apt to wear too rapidly and lose their points before the reproduction of a long sound record is completed. Also they are not-stiff enough to transmit the full volume of sound vibrations to the diaphragm of the sound box and by reason of the fragile character of the material used the-point engaging the record groove is sometimes broken away entirely when a high, loudnote is being reproduced.

T have discovered that a needle or stylus made of bone and properly treated will be free ,from all these disadvantages, give a true reproduction of full volume of tone devoid of scratching sounds, will not cut or wear the record tablet surface appreciably,

without resharpening. It can also e and will retain 'its point long enough to reproduce several sound records in succession resharpened'or reground to fit it for further use, after having its point deformed by the friction of contact with the sound record groove;

p The best method of carrying out my invention at Presentrknown to me is as folflows: ll take compressed bone, or horn,

which is an article of commerce occurring in the form of sheets or strips and which is formed from the bones or horns of cattle, and I cut or saw the same into rods of the requisite cross section. These are cut into proper lengths for use in the standard talking machine and given a tapering point at one end in any convenient manner. material in its raw state is somewhat porous or cellular in. structure, not of sufiicient hardness for the purpose and containing various earthy salts such as those of calcium,

sodium, magnesium, etc. As a result, a needle made of this material without further treatment would wear too rapidly and also.

scratch when rubbed along the sound record groove. .To remove these disadvantageous qualities 1 first harden the bone, preferably by immersing it for about an hour in a hardening bath, such as a saturated solution of chrom1c acid, which coagulates the gelatin forming an important constituent of the bone. The hardening process may be performed bythe alternative method of drying the bone slowly. Preferably I use for this purpose radiant heat such as is given oh by an electric heating block. The chromic acid treatment, however, gives the better results. The efl'ect of this portion of the treatment, performed in either manner, is to stifi'en the needle as a whole, and enhance its elasticity and capacity fortransmittingsound vibrations.

This

The second step of my process has for its object the removal of the earthy salts from that portion of the needle which is to come in contact with the sound record tablet. This I accomplish by immersing or washing the point of the needle in a dilute acid, such as a weak solution of hydrochloric acid. I find it sufiicient to thus treat the pointed end of the needle for a distance of about a quarter of'an inch from its extremity, and accomplish this by keeping it immersed to that extent in the acid bath for about an hour. This softens the immersed portion of the needle and dissolves out the earthy salts and other filling of that character from the pores or cells of the bone, but without destroying the shape of the needle point. The structure of the needle point and surfaces adjacent thereto is left in a soft, spongy, porous or cellular condition having a great capacity for absorption of fluids. I next immerse the point of the needle, which has been treated as above described, in a, liquid grease or oil.

So far I have obtained the best results from treatment with sperm oil.

needle can be resharpened a number of times.

before the oil saturated point or shell is en-. tirely removed. I have also found it ad- "antageous to give the shank or body of the needle a thin coating of rubber. This can be done by dipping it in a liquid rubber solution, after the other treatment above de-.

scribed has been completed. This enables the clamp of the stylus or needle holder to grasp the needle firmly and prevents chattering in the clamp.

The result of the above described process is a reproducer needle or stylus point which has a hard elastic core for transmitting sound vibrations, a tough, smooth, oily point for gliding over the sound record groove without scratching or wearing the surface of the tablet, and a slightly yielding, friction-producing clamping surface on its shank which enables the holding clamp to grasp it firmly without the exertion of crushing pressure, and without the possibility of chattering or rattlingat the points of contact.

Certain steps of the treatment above described could be omitted without entirely preventing the attainment of the results desired, and other materials might be substituted for some of those mentioned in certain of the operations set out, so long as the substituted materials operate in substantially the same manner to effect substantially the same result.

In the drawing which shows a side elevation of a needle made in accordance with myinvention, A, represents the body of the needle, B, the pointed end saturated with lubricating fluid and C, the rubber coating on the shank (shown in section) which may be used if desired, but is not absolutely necessary.

Having, therefore, described my invention, I claim:

1. The process of making a sound reproducing stylus which comprises the following steps, first, subjecting properly shaped pieces of compressed bone to a hardening treatment; second, treating the pointed end of the stylus so formed to an acid bath which dissolves out the earthy salts contained in the compressed bone, and third, saturating the porous structure left after the second step with a lubricating fluid.

2. The process of making a sound reproducing stylus which comprises the following steps, first, treating properly shaped pieces of compressed bone with a chromic acid solution; second, immersing the pointed end of the stylus so produced in a weak solution of hydrochloric acid, and, third, sat- 'urating the porous structure, left after the second step, with sperm oil.

3. A process of making needles for the sound reproducers oftalking machines which comprises the shaping of such needles out of a tough cellular or porous substance, the dissolving out of the contents of such pores or cells, and the reloading of the pores or cells with a heavy lubricating substance.

4. The product of the process herein described, being a reproducer needle for talking machines having a body of bone, and a polnt free from earthy materials with the pores or cells at and about said point loaded with a lubricating fluid.

5. The product of the process herein described, being a reproducer needle for talking machines having a body of compressed bone, and a point free from earthy materials with the pores and cells at and about said point loaded with sperm oil.

6. The product of the process herein described, being a reproducer needle for talking machines having a body of bone, and a point free from earthy materials with the pores or cells at and about said point loaded with a lubricating fluid, the shank of the needle being coated with rubber.

LEANDER J. WHITEMAN, JR.

Witnesses:

C. E. BOUQUEO, WALTER J. BURCHETT. 

